Flu Shots Are Effective in France

Since October 2025, several European countries have observed increases in influenza positivity rates among patients tested in community laboratories, beginning as early as week 41 of 2025.

According to a Rapid Communication published in Eurosurveillance (Volume 31, Issue 2), in France, the 2025/26 flu season is characterized by high circulation of influenza A(H3N2) viruses from subclade K, alongside co-circulation of A(H1N1)pdm09 subclade D.3.1.1.

 As of January 15, 2026, an early assessment of influenza vaccine effectiveness (VE) against laboratory-confirmed influenza using data from community laboratory surveillance through the first week of January 2026.

The overall interim VE estimate for individuals vaccinated from 15 days to 3 months before testing was 36.4% (95% CI: 29.7–42.5). Among the population aged ≥ 65 years, the point estimate was lower, peaking at 27.7% and overlapping with the 95% CI (16.7–37.3). 

These researchers concluded that despite a partial vaccine mismatch this season, interim analyses indicate a statistically significant vaccine VE across all age groups.

In the context of sustained influenza circulation in Europe, it is strongly recommended to reinforce vaccination uptake in the coming weeks.

This new data supports the U.S. CDC's recommendation that most visitors to France get an annual flu shot about two weeks before traveling abroad in 2026. Various flu shots are offered at travel clinics in the USA.